The selection of
residual pressure relief valve should follow the five principles of safety, scientificity, reliability, applicability and economy, as well as the requirements of working conditions on site, such as the size of valve diameter, working pressure, medium type, medium temperature, environment temperature, power supply voltage, connection mode, installation mode, valve body material, special options, etc. It is important to remember that we can help you and that we are always in touch with any technical needs.
Selection basis:
1. Selecting residual pressure relief valve according to pipeline parameters: diameter specification (DN), interface mode
1) Determine the diameter (DN) of the pipeline according to the requirement of the inside diameter or flow rate of the pipeline on site.
2) Interface mode, generally > DN50 should choose flange interface, and < DN50 can choose freely according to user's needs.
2. Selecting residual pressure relief valve according to fluid parameters: material and temperature group
1) Corrosive fluids: corrosion-resistant residual pressure relief valve and stainless steel should be selected; food-grade stainless steel residual pressure relief valve should be selected for super-clean fluids;
2) High temperature fluids: electromagnetic valves made of high temperature resistant electrical materials and sealing materials should be selected, and piston type structure should be chosen.
3) Fluid state: as large as gaseous, liquid or mixed state, especially when the diameter is larger than DN25, it must be distinguished.
4) Fluid Viscosity: Usually under 50cSt can be chosen arbitrarily, if more than this value, choose high viscosity residual pressure relief valve.
3. Selecting residual pressure relief valve according to pressure parameters: principle and structure
1) Nominal pressure: This parameter has the same meaning as other general valves and is determined according to the nominal pressure of the pipeline.
2) Working pressure: If the working pressure is low, the principle of direct-acting must be selected; when the minimum working pressure difference is above 0.1 Mpa, the direct-acting, step-by-step direct-acting and pilot-type can be selected.
4. Electrical selection: Voltage specifications should give priority to AC220V and DC24, which are more convenient.
5. Choose according to the duration of continuous working hours: Normal closure, Normal opening, or Sustainable power supply.
1) When the residual pressure relief valve needs to be opened for a long time and lasts longer than the closing time, the normal open type should be chosen.
2) If the opening time is short or the opening and closing time is not long, the normal closing type is chosen.
3) However, some working conditions used for safety protection, such as furnace and kiln flame monitoring, can not be open regularly, so long-term power-on type should be selected.
6. Select auxiliary functions according to environmental requirements: explosion proof, check, manual, waterproof fog, water spray, diving.
